From 2a0dfd8e2878ac37fe2c3a16a1a6753345d317a2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Tue, 7 Sep 2021 09:37:52 +0200 Subject: [PATCH] drm/amdgpu: fix use after free during BO move MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit c92db8d64f9e0313e7ecdc9500db93a5040c9370 upstream. The memory backing old_mem is already freed at that point, move the check a bit more up. Signed-off-by: Christian König Fixes: bfa3357ef9ab ("drm/ttm: allocate resource object instead of embedding it v2") Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1699 Acked-by: Nirmoy Das Reviewed-by: Michel Dänzer Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 3a55f08e00e1d..2335b596d892f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -513,6 +513,15 @@ static int amdgpu_bo_move(struct ttm_buffer_object *bo, bool evict, goto out; } + if (bo->type == ttm_bo_type_device && + new_mem->mem_type == TTM_PL_VRAM && + old_mem->mem_type != TTM_PL_VRAM) { + /* amdgpu_bo_fault_reserve_notify will re-set this if the CPU + * accesses the BO after it's moved. + */ + abo->flags &= ~AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED; + } + if (adev->mman.buffer_funcs_enabled) { if (((old_mem->mem_type == TTM_PL_SYSTEM && new_mem->mem_type == TTM_PL_VRAM) || @@ -543,15 +552,6 @@ static int amdgpu_bo_move(struct ttm_buffer_object *bo, bool evict, return r; } - if (bo->type == ttm_bo_type_device && - new_mem->mem_type == TTM_PL_VRAM && - old_mem->mem_type != TTM_PL_VRAM) { - /* amdgpu_bo_fault_reserve_notify will re-set this if the CPU - * accesses the BO after it's moved. - */ - abo->flags &= ~AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED; - } - out: /* update statistics */ atomic64_add(bo->base.size, &adev->num_bytes_moved);